Today, most film-projectors incorporated in movie theatre auditoriums utilize lamps that output approximately 15,000 lumens of light. Lamps that output in excess of approximately 15,000 lumens of light cause ‘celluloid’ film to disintegrate and melt because of the heat buildup associated with illuminating film. Because of the relatively low level of light output from old-fashioned film projectors; there is a natural limit to the size of the screen onto which filmed content may be projected without becoming so dim as to become undecipherable.
Newer generation digital projectors are now available that are capable of generating approximate 25,000 lumens of light. Three of these projectors can be stacked on top of one-another or can be placed side-by-side (all projecting precisely the exact digital image) to attain up to approximately 75,000 lumens of light. These projectors are very well suited for the exhibition of blockbuster movies, television and CATV content, and immersive advertising either ‘live’ or from pre-recorded mediums onto large screens. However, because of the economic constraints of constructing large, column-free, free-span, air-conditioned envelopes around such large screens, there are no indoor auditoria in the United States capable of accommodating such screens. It is possible, however, to project images on such a large screen without sustaining the economic burden of constructing large, column-free, free-span, air-conditioned envelopes by projecting the images in an outdoor, open-air theater.